There is a need for ammunition capable of being fired from a sidearm or other lightweight firearms which has high muzzle velocity, great penetrative power and excellent accuracy. None of these characteristics is found in present ammunition types suitable for firing from a sidearm or other light weight firearms. The need is particularly great in police forces and special forces. Body armour which is currently available makes most sidearms ineffective. However, in many cases a rifle, which would provide the penetrative power necessary is not suitable, simply because it cannot be drawn quickly enough, and can be difficult to conceal.
It is well understood by those skilled in the art of weaponry that firearms fall into four separate families, those being:
a) Small calibre weapons using ammunition ranging in size from 0.22 inch which are commonly fired from small handguns; PA1 b) Small arms weapons which use straight sided centre fire ammunition, the ammunition being fired from handguns and semi-automatic guns, the common bores being 0.38 inch, 0.357 inch, 0.44 inch, 9 mm and 10 mm which offer accuracy over a range up to 50 meters; PA1 c) Combat rifles which fire ammunition sending projectiles at very high velocities over ranges of 500 meters plus, the common bores being 0.223 inch (5.56 mm), 5.7 mm, 0.303 inch, 7.62 mm and 0.50 inch; and PA1 d) Heavy weapons for firing ammunition up to 2 kilometers commonly having bores of 20 mm, 30 mm and larger, and which are used in extreme range combat to deliver large payloads, e.g. anti-tank and anti-aircraft ammunition.
Small arms and small calibre weapons are convenient simply because they are small and lightweight, which makes them easy to use and carry about the person. However, the performance of these types of weapon is limited. They cannot fire projectiles over long distances, and furthermore are very inaccurate at anything more than short distances. In general, pistol ammunitions have projectiles of a diameter which corresponds to the internal diameter of the cartridge case, the walls of the cartridge case being parallel, whereas rifle ammunitions have projectiles significantly smaller in diameter than the cartridge cases to which they are attached. The result is a projectile which travels further and is more accurate. The cartridge cases of known rifle ammunitions are much longer than the cartridge cases for automatic and semiautomatic sidearm type weapons.
The types of wound produced by standard pistol and rifle ammunitions are quite different. Pistol ammunition produces low velocity wound characteristics, characterised in animals by the destruction of tissue in the path of the projectile, and a minor amount of secondary cavity damage around the path of the projectile. It is the effect of the projectile destroying objects in its path which neutralises the target. On the other hand, rifle ammunition produces high velocity wounding where it is not only destruction of tissue by the projectile which causes neutralisation, but primarily damage to tissues caused by a velocity induced shock wave. The projectile itself causes limited damage, but it is the shock wave induced by the projectile which results in severe trauma damage, sometimes known as temporary cavity damage. It is understood that a projectile must hit a target when travelling at velocity of at least 518 meters per second for high velocity wounding to occur.
Single shot pistols, often being of bolt action type have been adapted to receive a rifle cartridge. However, it would be desirable to produce ammunition suitable for a standard sidearm or other lightweight firearms capable of producing high velocity wounding in a target.
Many attempts have been made to optimise the performance of small arms and small calibre weapons. Each time the result has been a larger weapon. For example the Calico made by Calico Arms, and the P90 made by FN. Although both of these weapons increase the accuracy and distance of the projectile fired, both have disadvantages. The only known ammunition for use in sidearms which utilised a projectile of smaller diameter than the internal diameter of the cartridge case to which it was attached was the Mauser Parabellam, which consisted of a projectile having an external diameter of 7.65 mm attached to a case having an external diameter of 9.6 mm. Whilst improved velocity and penetrative capacity were noted, this ammunition still produced low velocity wound characteristics.
Many of the improved weapons also suffer problems in their re-arranged feed mechanisms and magazines.
The constraints of a small automatic or semi-automatic weapon mean that small compact ammunition having a short case length is required. Assuming that the weapon is to provide a reasonable number of shots then the ammunition will generate a low velocity, have drastically reduced terminal effects, and produce problems with terminal effects as a result of its small size.
The problem in controlling the burn characteristics of the powder in cartridge cases suitable for use in automatic or semi-automatic sidearms have lead those skilled in the art to develop ammunition having parallel sides. However, there is a need for police officers to be provided with firearms having penetrative power greater than that which sidearms can presently provide but which are easier to handle than conventional rifles.
There is a limit velocity above which a projectile of a given diameter will cause a high velocity wound in an animal, and the term "limit velocity" shall be understood to mean the velocity at or above which the projectile in question causes high velocity wounding.
It would therefore be desirable to provide ammunition capable of being fired from a sidearm which has a longer range and gives greater accuracy than currently available ammunition. It would also be desirable to provide a firearm suitable for, or to modify parts of existing firearms to make them capable of, firing such ammunition.
It would be advantageous to be able to utilise commonly available projectiles, for example projectiles made from lead which could be copper jacketed. It would also be advantageous to be able to utilise commonly available cartridge cases.
Furthermore, it would be desirable to provide ammunition for a self-loading, automatic or semi-automatic, sidearm capable of firing the projectile at a velocity in excess of the limit velocity for the said projectile.
The term sidearm shall be understood to mean pistols or sub-machine guns.
The term self-loading shall be understood to mean semi-automatic or automatic feed mechanisms.